The present invention relates to a vehicle wheel and in particular to a wheel which includes a rigid, circumferentially-extending support surface mounted on a radially extending member to provide a support surface for emergency deflated running of the tire.
A particular problem with wheels of this type particularly when the rim is of one piece tire, is to provide for assembly of a tire to the wheel and this becomes even more difficult with small sizes where the rim widths are limited.
The present invention has the object of providing for improved assembly.
According to one aspect of the present invention a wheel is provided which comprises a pair of parallel, circumferentially extending, axially spaced-apart, radially outwardly facing bead seats. Adjacent to and axially outwards of each bead seat is disposed a radially outwardly projecting tyre retaining flange. A tire fitting well is provided between the bead seats and a substantially rigid, deflated tire support surface radially outwardly of the bead seats mounted upon a support member projecting radially from the well whereby the support member is positioned at one side of the well, considered in axial cross section of the wheel rim, around part of the circumference of the wheel rim and at the other side of the well around the remainder of the circumference so that tire fitting is facilitated.
Preferably the support member is at one side of the well for half the circumference of the wheel rim. The support member may be separate to the wheel rim and detachably fastened thereto. More preferably, the support member is integral with the wheel rim so that a one piece wheel rim assembly is provided. This avoids assembly of an incomplete wheel with a tire.
The actual width of the well may be substantially less than the width of the two tire beads for which the wheel rim is designed because half the circumference of the well is availale for each of the beads.
Preferably bead retaining formations are provided adjacent to each bead seat immediately axially inwards of the bead seats. The retaining formations may be humps or a circumferentially extending groove formed in the wheel rim to provide a projecting toe on a tire designed for the wheel rim. Such tires are known in the industry as TD tires.